Topic 9: Forces and their effects

• What is Newton's Third Law of Motion?

  For every action, there is an equal and opposite reaction.
• What do the rules of forces state?

  Forces are equal and opposite, must act on different objects, and must be of the same type.
• What happens when two objects interact with each other?

  They exert force on each other.
• What are the two categories of forces?

  • Contact forces
  • Non-contact forces
• What are examples of contact forces?

  Friction and air resistance.
• What are examples of non-contact forces?

  Magnetism, gravitational attraction, and electricity.
• What does a balanced force mean?

  Forces are equal and opposite, acting on the same object, and are of different types.
• What is the result of balanced forces on an object?

  The object is in equilibrium.
• What does it mean when an object is at rest or moving with constant velocity?

  The net force acting on the object is zero.
• What is the process for resolving forces?

  1. Choose a scale.
  2. Link the vectors head to tail.
  3. Draw the resultant vector using the triangle or parallelogram method.
  4. Measure the length of the resultant vector (put it to scale).
  5. Measure the angle of the resultant force.
• What are free body diagrams used for?

  To model the forces acting on an object.
• How is each force represented in a free body diagram?

  As a vector arrow scaled to the magnitude of the force, pointing in the direction it acts, and labeled with the force's name.
• What can free body diagrams help identify?

  Forces acting on an object and the net force in a particular direction.
• How can two forces be combined to find the resultant force?

  By adding them together using a scale drawing when they are not at a right angle.
• What is the triangle or parallelogram method used for?

  To draw the resultant vector when adding two vectors.
• What is the first step in resolving forces using a scale drawing?

  Choose a scale.
• What should you do after linking the vectors head to tail?

  Draw the resultant vector.
• What do you do after measuring the length of the resultant vector?

  Measure the angle of the resultant force.
• What does each arrow in a free body diagram represent?

  Each arrow represents a force acting on the object.
• How does a free body diagram help in physics?

  It helps visualize and analyze the forces acting on an object.